Sheet holding and transfer mechanism for presses



w. G. YOUNG 3,096,088

SHEET HOLDING AND TRANSFER MECHANISM FOR PRESSES July 2, 1963 Filed March 20, 1961 WILLIAM G. YOUNG 3,096,983 SI'EET HOLDING AND TRANSFER MECHANISM F812 PRESSES William G. Young, Pittsburgh, Pa, assignor to Miller Printing Machinery Co., Pittsburgh, Pa, a corporation of lennsylvania Filed Mar. 20, 1961, Ser. No. 97,916 3 Gaines. (Cl. 271-511) This invention relates to sheet holding and transfer mechanisms for presses and particularly to sheet holding mechanisms for tightening and holding sheets of paper on presses such as multi-color perfector presses. The transfer cylinders of presses such as the multi-color press illustrated and described in Gegenheirner et al. Patent 2,757,610 are frequently provided with suction heads which are used to hold the end of a sheet onto the cylinder during rotation and transfer. These suction heads are fixed and the paper sheet must be delivered to them in a flat and taut condition in order to carry the sheet in smooth unwrinkled form. There is no provision for tightening or stretching the sheet once it reaches the transfer cylinder.

I have invented a suction head and transfer cylinder which not only engages and holds the end of the sheet but also stretches the sheet into a smooth taut condition on the cylinder.

Preferably I provide in a transfer cylinder having means receiving the leading edge of a sheet to be transfer-red, spaced openings in the periphery thereof at the trailing edge of said sheet, connections in said openings to a source of suction, a suction head in each opening slidable in the periphery of the cylinder, resilient means normally urging said head toward the means receiving the leading edge of the sheet, connections in said suction head to the suction connections in said openings whereby the trailing edge of a sheet is engaged onto the suction head and the suction head is then moved against the resilient means to draw the trailing edge of the sheet tautly over the peripheral surface of the cylinder. Preferably the suction head has a foraminous surface over a suction chamber and is mounted for telescopic movement on a hollow arm fixed to a main body portion. The main body portion is fixed in the opening sealingly connected to the suction connections therein.

Preferably the transfer cylinder is provided with gripping fingers for the leading edge of the sheet and with suction valving and radial yoke connections such as are disclosed in the aforementioned Gegenheimer Patent No. 2,757,610.

In the foregoing general description I have set out certain objects, purposes and advantages of my invention. Other purposes, objects and advantages will be apparent from a consideration of the following description and the accompanying drawings in which:

FIGURE 1 is a simplified transverse section of a preferred embodiment of a transfer cylinder and suction head of my invention;

FIGURE 2 is an enlarged end View of the suction head of FIGURE 1;

FIGURE 3 is a section through the suction head taken on line IIIIII of FIGURE 2;

FIGURE 4 is a plan view of a transfer cylinder with suction heads according to my invention showing schematically the direction of motion;

FIGURE 5 is an exploded isometric view of the suction head of FIGURE 2;

FIGURE 6 is a side view of a second embodiment of suction head according to my invention.

Referring to the drawings I have illustrated a transfer cylinder 10 mounted on a shaft 11. Gripper fingers 12 are mounted on the periphery to grip the leading edge of a sheet 13. The gripper fingers 12 are identical with gripper G4 of Patent 2,757,610 and their operation is the same. It is accordingly not deemed necessary to describe the operation of the gripper fingers 12 in detail. Radially extending hollow spokes 14 each have a central bore 15 which terminates in an opening 16 in the periphery of the transfer cylinder 1% The hollow spokes 1'4 correspond to spokes 24 1 of Patent 2,757,610 and are connected through valves to a source of suction as described in the aforesaid patent. Each of the openings 16 is adapted to receive a removable suction head base member 17 held in place by screws 18 at each end. The base member 17 is provided with a radially extending flange 19 carrying a transverse arm 20 preferably in the form of a cylinder. The arm 20 is provided with an axial bore 21 communicating through passage 22 in the flange 19 with passage 23 in the base member 17 which in turn communicates with the central bore 15 of spoke 14. A suction head 25 with foraminous sheet contacting face 26 receives the arm 20 in a bore 27 communicating through passage 23a with chamber 28 beneath the foraminous face 26. A spring 29 in bore 27a bears against the end of bore 21 centrally of arm 20 urging the suction head away from flange 19. The foraminous contacting face 26 is provided with an extending lip 30 which extends over flange 19 and with the face 26 lies in the surface of the periphery of the transfer cylinder 10.

The operation of this device is as follows. When the leading edge of a sheet 13 is engaged by gripper fingers 12 in the manner described in Patent 2,757,610 and the transfer cylinder is rotated on its axis the trailing edge of the sheet is delivered over the foraminous surface or face 26 of the suction head. Suction applied to the head 25 through bore 15, passages 22 and 23 and bore 21 acts through chamber 28 and the foraminous face 26 to draw the trailing edge onto the face 26. When this occurs the suction causes the head 25 to move on arm 20 into contact with flange 19. This draws the trailing end of sheet 13 in a direction away from the gripping fingers 12 and stretches it tautly over the surface of transfer cylinder 10. When the suction is released the spring 29 returns head 25 to its original position.

In FIGURE 4 I have illustrated the use of four suction heads in spaced relation across the sheet. The two center heads 25b and 25c move parallel to the end of the transfer cylinder (as indicated by the arrows) and the two end heads 25:: and 25d moving angularly toward the nearest end of the cylinder (as indicated by the arrows) so as to stretch the paper both lengthwise and widthwise over the cylinder.

In the embodiment shown in FIGURE 6, I have illustrated a suction head whose structure and operation are substantially identical with that of FIGURES 1 through 5 except that the flange extends to the surface of the periphery of the cylinder 10a and the foraminous face 26a has no extension lip to move over the flange 43.

While I have illustrated and described certain presently preferred embodiments of my invention it will be rec- 3 ognized that this invention may be otherwise embodied within the scope of the following claims.

I claim:

1. In a sheet handling device, a sheet transfer cylinder having means fixed relatively to the cylinder receiving and gripping the leading edge of a sheet to be transferred and valved suction means extending to the periphery of the cylinder adjacent the trailing edge of the sheet to be transferred, an opening in the periphery of the cylinder at the suction means, a suction head in said opening for engaging the trailing edge of said sheet, said suction head being slidable generally on the circumference of said cylinder, resilient means normally urging said head toward the gripping means, connections in said suction head to the suction means acting through the suction head to engage the trailing edge of the sheet and thereupon draw the head against the resilient means whereby to draw the sheet taut over the periphery of the cylinder.

2. A suction head adapted to be inserted in an opening in the periphery of a transfer cylinder having a suction connection comprising a base member having a radially extending flange terminating intermediate the periphery of the cylinder and the bottom of said opening, a hollow arm extending transversely from said flange, a movable suctionhead on said base telescoping sealingly on said arm, resilient means on said arm urging the head away from the flange, a foraminous surface on .said suction head having an extension adapted 'to move above the flange, said surface lying in the periphery of the cylinder and connections from the foraminous surface through the hollow arm to the suction connection in the opening whereby the fo'raminous surface is adapted to engage a sheet and thereafter the head is telescoped over the arm against the resilient means.

3. In a sheet handling device, a sheet transfer cylinder having means fixed relatively to the cylinder receiving and gripping the leading edge of a sheet to be transferred and valved suction means extending to the periphery of the cylinder adjacent the trailing edge of the sheet to be transferred, spaced openings across the surface of the transfer cylinder equally spaced from the gripping means, a movable suction head in each said opening adapted to move toward and away from said gripping means, the outermost head being adapted to move angularly towards the nearest adjacent edge of the cylinder, resilient means normally urging said head toward the gripping means, connections in each said suction head to the suction means acting through the suction head to engage the trailing edgeof the sheet and move said suction head against the spring whereby to draw the sheet taut over the periphery of the cylinder.

4. In a sheet handling device, a sheet transfer cylinder having gripping means fixed relatively to the cylinder for receiving and gripping the leading edge of a sheet, a base member carried by the cylinder at the periphery thereof, a conduit extending to and communicating with the base member, a suction head movable along the base member having a sheet engaging portion disposed adjacent the trailing portion of a sheet whose leading edge is gripped by the gripping means and means for creating suction in the conduit and hence in the base member and through the base member to the sheet engaging portion of the suction head to attract by suction the trailing portion of the sheet and thus attach the trailing portion of the sheet to the suction head, the base'member and suction head having means whereby the suction head is moved generally away from the gripping means when the trailing portion of a sheet is attached by suction to the sheet engaging portion of the suction head to draw the sheet taut over the surface of the cylinder between the gripping means and the sheet engaging portion of the suction head.

5. In a sheethandling device, a sheet transfer cylinder rece ing and gripping the leading edge of a sheet, a base member carried by the cylinder at the periphery thereof, a conduit extending to and communicating with the base member, a suction head movable along the base member having a sheet engaging portion disposed adjacent the railing portion of a sheet whose leading edge is gripped by the gripping means, means for creating suction in the conduit and hence in the base member and through the base member to the sheet engaging portion of the suction head to attract by suction the trailing portion of the sheet and thus attach the trailing portion of the sheet to the suction head, the base member and suction head having means whereby the suction head is moved generally away from the gripping means when the trailing portion of a sheet is attached by suction to the sheet engaging portion of the suction head to draw the sheet taut over the surface of the cylinder between the gripping means and the sheet engaging portion of the suction head, and means for m0ving the suction head generally toward the gripping means after the trailing portion of the sheet has been detached from the sheet engaging portion of the suction head.

6. In a sheet handling device, a sheet transfer cylinder having gripping means fixed relatively to the cylinder for neceiving and gripping the leading edge of a sheet, a base member carried by the cylinder 'at the periphery thereof, a conduit extending to and communicating with the base member, a suction head movable along the base member having a suction chamber and perforated sheet engaging portion disposed adjacent the trailing portion of a sheet whose leading edge is gripped by the gripping means and means for creating suction in the conduit and hence in the base member and through the base member to the suction chamber and sheet engaging portion of the suction head to attract by suction the trailing portio-n'of the sheet and thus attach the trailing portion of the sheet to the suction head, the base member and suction head having means whereby the suction head is moved generally away from the gripping means when the trailing portion of a sheet is attached by suction to the sheet engaging portion of the suction head to draw the sheet taut over the surface of the cylinder between the gripping means and the sheet engaging portion of the suction head.

7. In a sheet handling device, a sheet transfer cylinder having gripping means fixed relatively to the cylinder for receiving and gripping the leading edge of a sheet, a base member carried by the cylinder at the periphery thereof, -a conduit extending to and communicating with the base member, a suction head movable along the base" member having a perforated sheet engaging portion disposed adjacent the trailing portion of a sheet whose lead ing edge is gripped by the gripping means and means for creating suction in the conduit and hence in the base member and through the base member to the sheet engaging portion of the suction head to attract by suction the trailing portion of the sheet and thus attach the trailing portion of the sheet to the suction head, the base member and suction head having suction operated means whereby the suction head is moved generally away from the gripping means when the trailing portion of a sheet is attached by suction to the sheet engaging portion of the suction head to draw the sheet taut over the surface of the is gripped by the gripping means, means for creating suction in the conduit and hence in the base member and through the base member to the sheet engaging portion of the suction head to attract by suction the trailing portion of the sheet and thus attach the trailing portion of the 5 6 sheet to the suction head, the suction head being movable ing the suction head generally toward the gripping means on the base member by suction generally away firorn the after the trailing portion of the sheet has been detached gripping means when the trailing portion of a sheet is atfrom the sheet engaging portion of the suction head. tachfed by Suction to Sheet engaging Portion. of the References Cited in the file of this patent suctlon head whereby the perforated sheet engaging por- 5 tion is closed to draw the sheet taut over the surface of UNITED STATES PATENTS the cylinder between the gripping means and the sheet 2,384,231 Bamford Sept. 4, 1945 engaging portions of the suction head, and means for mov- 2,571,805 Wood Oct. 16, 1951 

1. IN A SHEET HANDLING DEVICE, A SHEET TRANSFER CYLINDER HAVING MEANS FIXED RELATIVELY TO THE CYLINDER RECEIVING AND GRIPPING THE LEADING EDGE OF A SHEET TO BE TRANSFERRED AND VALVED SUCTION MEANS EXTENDING TO THE PERIPHERY OF THE CYLINDER ADJACENT THE TRAILING EDGE OF THE SHEET TO BE TRANSFERRED, AN OPENING IN THE PERIPHERY OF THE CYLINDER AT THE SUCTION MEANS, A SUCTION HEAD IN SAID OPENING FOR ENGAGING THE TRAILING EDGE OF SAID SHEET, SAID SUCTION HEAD BEING SLIDABLE GENERALLY ON THE CIRCUMFERENCE OF SAID CYLINDER, RESILIENT MEANS NORMALLY URGING SAID HEAD TOWARD THE GRIPPING MEANS, CONNECTIONS IN SAID SUCTION HEAD TO THE SUCTION MEANS ACTING THROUGH THE SUCTION HEAD TO ENGAGE THE TRAILING EDGE OF THE SHEET AND THEREUPON DRAW THE HEAD AGAINST THE RESILIENT MEANS WHEREBY TO DRAW THE SHEET TAUT OVER THE PERIPHERY OF THE CYLINDER. 